Complete DFG-8 adapter proposal support

src/docforge/project.py

@@ -7,6 +7,7 @@ import json
 import subprocess
 import tomllib
 from collections import Counter
+from collections.abc import Mapping
 from dataclasses import replace
 from pathlib import Path
 from typing import Any
@@ -500,6 +501,46 @@ def validate_graph(nodes: tuple[Node, ...], edges: tuple[Edge, ...]) -> None:
         visit(node_id, ())
 
 
+def validate_source_layout(nodes: tuple[Node, ...]) -> None:
+    """Validate the generic Markdown and TOML source-layout contract."""
+
+    markdown_sources: dict[str, list[str]] = {}
+    anchors: dict[tuple[str, str], list[str]] = {}
+    for node in nodes:
+        if Path(node.source_path).suffix == ".md":
+            markdown_sources.setdefault(node.source_path, []).append(node.node_id)
+            continue
+        if not node.source_anchor:
+            raise DocForgeError(
+                "source_anchor_required",
+                "TOML nodes require a stable source anchor",
+                node_id=node.node_id,
+            )
+        anchors.setdefault((node.source_path, node.source_anchor), []).append(node.node_id)
+    markdown_conflicts = {
+        source: sorted(node_ids)
+        for source, node_ids in markdown_sources.items()
+        if len(node_ids) > 1
+    }
+    if markdown_conflicts:
+        raise DocForgeError(
+            "source_conflict",
+            "Markdown sources may contain only one node",
+            sources=markdown_conflicts,
+        )
+    anchor_conflicts = [
+        {"source": source, "source_anchor": anchor, "nodes": sorted(node_ids)}
+        for (source, anchor), node_ids in sorted(anchors.items())
+        if len(node_ids) > 1
+    ]
+    if anchor_conflicts:
+        raise DocForgeError(
+            "source_anchor_conflict",
+            "TOML source anchors must be unique within their source",
+            conflicts=anchor_conflicts,
+        )
+
+
 def _revision(root: Path) -> str:
     try:
         result = subprocess.run(
@@ -588,7 +629,7 @@ class Project:
             digest.update(relative.encode())
             digest.update(b"\0")
             digest.update(hashlib.sha256(captured[path]).digest())
-        digest.update(b"docforge-core:0.5.0:index:1")
+        digest.update(b"docforge-core:0.6.0:index:1")
         return ProjectSnapshot(
             descriptor=self.descriptor,
             nodes=ordered_nodes,
@@ -617,3 +658,14 @@ class Project:
         if not ordered_sources:
             raise DocForgeError("empty_project", "No canonical Markdown or TOML sources were found")
         return tuple(ordered_sources)
+
+    def validate_proposal(
+        self,
+        base: ProjectSnapshot,
+        projected: ProjectSnapshot,
+        operations: tuple[Mapping[str, object], ...],
+    ) -> None:
+        """Generic sources require no policy beyond the core proposal validation."""
+
+        del base, operations
+        validate_source_layout(projected.nodes)